292 



HOW CROPS GROW. 



wards outwards and downwards, and hence the designa- 

 tion endogenous, which in plain English means inside- 

 grower. 



In consequence of this inner growth, the stems of 

 most woody endogens, as the palms, after a time become 

 so indurated externally that all lateral expansion ceases, 

 and the stem increases only in height. In some cases, 

 the tree dies because its interior is so closely packed with 



Fig. 4& 



bundles that the descent of new ones, and the accom- 

 panying vital processes, become impossible. 



In herbaceous endogens the soft stem admits the 

 indefinite growth of new vascular tissue. 



